Overheating

[rockdrummer027]

My car has been running warm but only on the highway at sustained high rpm's. Even quick acceleration around town won't make it run hot. On my way home from work today it really got hot and when i popped the hood the coolant was boiling. Where should i start? Thermostat? Radiator Cap?

[Def]

What kind of water temps at the outlet are you talking about when you say "warm" or "hot?"

[rockdrummer027]

Well warm is 1 line above normal which is the 3'rd line on the stock gauge but hot is all the way up on the gauge.

[rockdrummer027]

Also, my heat usually works but when the coolant boiled today... no heat.

[Def]

Ok, first of all - stock gauge = garbage. You can be hitting over 220*F coolant temps and it never moves - not good.

That said, your symptoms sound like a stuck thermostat, and it's very easy to replace. Make sure you properly bleed the coolant(this involves opening the bleed screw).

[Def]

Oh yea, get a Nissan thermostat - don't EVER get any coolant system parts from an autoparts store. I can't tell you how many times I've seen those cheap pieces blow up/stick open/stick closed/fail/blow engines etc.

[rockdrummer027]

Thanks for the advice. Should I try bleeding the coolant first without changing the thermostat because I read that air in front of the thermostat can delay its opening.

[Epstein]

If your heat wasn't working, then you definitely had air in the lines somewhere. If you do bleed the system, do it with the heater on high.

[rockdrummer027]

Upon closer inspection i noticed there's no belt on the water pump and alternator. The other two belts are there but that one is completely gone. I suppose the belt was weak and not turning the pulley consistently causing slightly elevated water temperatures and then it broke and the car really overheated. I can't even figure out how to get at the bolts for the thermostat housing on the SOHC with all of its hoses and lines and crap and now I have to learn how to change belts. This car is certainly teaching me quite a bit.

[Invisible_Saddle]

I changed that same belt in the parking lot of an autozone when my belt went out on the fwy. Simple tools to make slack on the first belt. and that belt does fit around stock clutch fan.